Body Composition 001: The Guide You Need To Read Before All Else

Time to read 5 min

In recent times, fitness enthusiasts and trainers alike have abandoned the BMI for body composition. There is reason to believe that body composition captures the picture of fitness than BMI which just measures the height to weight ratio in a scientific manner. 


Are you, however, too embarrassed to ask what body composition is? 

From the whats to the hows and whys, we will take you through the process of measuring and tracking a parameter that can be elusive to capture at times, but is very dependable otherwise. 


  • As the name suggests, body composition is basically what the body is made up of. A human body is made up of fats, muscles, tissues, proteins and water.
  • After several studies, we have ideal parameters for each of these components.
  • Components are measured as a percentage to reflect what part they play in the whole system. For example, a fat percentage of 20% means that about 20% of your body weight comes from fat. 

Measuring Body Composition 

Like so much else in the fitness domain, body composition has followed the 2C or 2 component model for a long time. This model measures just two parameters- fat mass (FM) and fat free mass (FFM). 


  • This measurement is great for people whose only concern is losing weight. A falling FM and an FFM that rises correspondingly are enough to tell you that you are steadily losing weight and keeping it off.

However, a more sensitive and sophisticated model is now available for body composition, and this takes into account the fact that the body needs several different components to work. 


  • Water: Humans are basically water. If not for the skeleton and muscles that give us structure, we would have been shapeless globs. Body water can show us how much water we have, and how much we have unnecessarily retained in the body because of bad food and lifestyle choices.
  • Protein: All muscles are made up of proteins, which is why they are called the building blocks of the human body. Measuring protein is a way of measuring your muscle mass.
  • Fat: Contrary to popular belief, we shouldn’t be aiming for a negligible fat percentage. Fat is the body’s store of energy that helps us get through each day without needing a meal every hour or so. 

This model is known as the 4C model and it takes into account all of the basic blocks that make us up. 

Seems like a huge bother, doesn’t it? Why even measure body composition? Why not just stick to BMI instead? 

The Case For Body Composition Analysis 

Have you heard of the age-old problem about which weighs more- a kilo of cotton or a kilo of iron? Well, both do weigh the same. But which occupies more space? Cotton, of course. Muscle and fat are a bit like that. A kilo of fat is much more visible in the body, and takes up more space too. 


Now, if you measure just BMI, and you are within the healthy weight range, you may still have more fat than is desirable for a healthy human being. Worse, there is no way to identify this problem either. 


On the other hand, body composition analysis can tell you exactly how much you have of what. If you exercise more often, you will tend to have more muscle mass. If you lead a fairly sedentary life, but still look healthy, you may ne harbouring more fat than you need. Remember, more muscle equals better metabolism, and more fat equals worse metabolism. 


Okay, but I can just stand on a scale to get my BMI. Wouldn’t I need to see a specialist to measure body composition? 

Measuring Body Composition 

The simple answer is yes, you have to meet a specialist if you’re serious about the analysis and its results. Thankfully, some easy ways of measuring do exist. Let them be the starting point, and you can go for more sophisticated testing later. 


  • Calipers: You would have last encountered these in a science lab, but calipers are a great measure of the 2C model. They pinch the fat from different parts of your body and measure how much tissue is hanging out. Crude, but effective, for a while.
  • Hydrostatic measures: When weighed in water instead of on land, you weigh lesser. By fully immersing yourself in water and exhaling fully, your weight is a good measure of the things that make you float vs the things that keep you down. This is a professional test and must be done under supervision.
  • DEXA: In this test, X-rays are sent through the body and their energy upon leaving the body is compared to their initial energy. This test is well-standardized and can be replicated anywhere with the right machinery. 

These are just some of the many testing methods available today. Most people begin measuring with calipers and then move on to other tests. But the question arises, “Do I need this test?” Surely, not everyone is an athlete, so why measure body composition at all? 


Athlete or not, our bodies are made up of the same building blocks, and using a holistic measure tells us where we stand in terms of fitness. And fitness is a goal for everyone too- people with more body fat are susceptible to cardiovascular disease and diabetes. 


  • Children: For children, body composition is a wonderful way to understand nutritional excesses and deficiencies. Reduced body fat as measured by DEXA is an indicator of malnourishment. Likewise, India is second only to China in the number of obese children, an indicator of a progressively sedentary lifestyle. Measuring body composition can tell us how to address these concerns. 
  • Adolescents: Like in children, body composition is a sure sign of malnourishment. Also, in late adolescence, some children show an inclination towards sports. Measuring body composition in them helps to understand their needs and requirements better. 
  • Athletes: Athletes have the most to gain from body composition analysis. If they have increased fat, they are unlikely to perform as efficiently as they would like to. If they have low muscle mass, they need to work to improve it. 
  • Sedentary people: Most adults fall into this bracket. In otherwise healthy subjects who are not obese, it has been observed that exercising for just three weeks helped reduce the FM without affecting the FFM severely. This applied to both men and women. In the absence of diet control, exercise is the best way to lose weight. 
  • Older adults: Parameters of measuring body composition vary in the elderly. They don’t have the same muscle mass as younger people. However, body composition analysis can point to nutritional gaps, as well as the risk they have for developing chronic illnesses. 

And this is why body composition analysis is for everybody! Even if you do it just for fun, there is something you can learn about your body and yourself.


* Medical Disclaimer - The following information is for educational purposes only. No information provided on this website, including text, graphic, and images, are intended as substitutes for professional medical advice. Please consult with your doctor about specific medical advice pertaining to your condition(s). 

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